577r Monitoring, Detection and Diagnosis of Leaks from Gas Pipes Based on Real-Time Data Collected Over the Ubiquitous Sensor Network

Dongil Peter Shin, Dept. of Chemical Engineering, Myongji University, Nam-Dong, Yongin, Kyunggido, 449-728, South Korea and Jae Wook Ko, Dept. of Chemical Engineering, Kwangwoon University, Wolgye-Dong, Nowon-Ku, Seoul, 139-701, South Korea.

As the world's second largest LNG importer, South Korea imports most of its LNG from Indonesia, Qatar, and Oman with smaller volumes from Malaysia, Brunei, the UAE, and Australia. South Korea has three regasification terminals owned and operated by state-owned Korea Gas Corporation (KOGAS) at Pyeongtaek, Incheon, and Tongyeong. Natural gas is mainly supplied to city gas companies and power generators. With three terminals and eight district offices nationwide, KOGAS is supplying natural gas to every corner of the country.

LNG is stored in storage tanks at three receiving terminals. After going through a gasification process, it is distributed nationwide through an extensive pipeline network. The operating branches, which receive natural gas from the terminals, supply it stably to 17 power stations of 10 power companies and 30 city gas firms. As natural gas is supplied to end users through pipelines, effective operation of a network of pipelines is crucial. By completing the pipeline to Gangwon province in 2002, after starting construction of the natural gas pipeline network in the Seoul metropolitan area in 1983, KOGAS had constructed a ring-shaped 2,520km supply network linking the whole nation. This network allows for safe and convenient use of natural gas around the clock anywhere on the peninsula.

For many years, Korea has proven to be a trailblazer in the information-technology sector. And the country won't likely stop until it attains its ultimate vision of creating a "ubiquitous" society where people can connect to the web, television and other services anytime, anywhere. Korea's central and local governments, as well as businesses, have begun to test out the possibilities of creating that visionary state through "u-city" or ubiquitous city projects. U-city is intended to give its residents not only a more convenient lifestyle but also more secure, safe, environmentally-friendly and humane way of life. This will be achieved by integrating the latest IT infrastructures and information services into urban space. Technologies that are likely to be featured in u-cities include broadband convergence network, radio frequency identification, ubiquitous sensor network, home networking, WiBro, digital multimedia broadcasting, telematics, geographic information system, location-based system, smart card system and video conference technologies.

By using its advanced IT, Korea is trying to improve the security of its energy infrastructure and the safety in everyday's energy use around the country. In this presentation, we will give an overview of a government-sponsored research on the monitoring, detection and diagnosis of releases from gas pipes, based on real-time data collected over the ubiquitous sensor network. A ubiquitous sensor network covering the city gas pipe network is to be installed for the sensor-network based source tracking. Fixed sensors and mobile sensors, if necessary, send operational information at designated points over the network and measured concentrations of gases in real-time.

From the real-time sensor data including flow rates, acoustic emission signals, and gas concentrations, we monitor, detect and analyze the suspected location and magnitude of gas releases. The type and amount of the release and its location on the GIS map are tracked relying on a combination of diagnostic methods and massive computation of dispersion models. Warnings are generated and corresponding emergency responses are executed based on the result of the simulation of the expected dispersion consequences, by combining the sensor data, meteorological information, GIS data and the diagnostic result of the source term. A prototype system of the proposed framework is being tested against the simulated sensor data. In addition to the enhanced security of the energy infrastructure, the result of this study will help improving the confidence of residents living next to storage, handling and transporting facilities of hazardous materials, by supplying the improved real-time emergency response plan and monitoring system for various hazardous gas releases.